This is from memory, as far as I know nobody in the family ever wrote it down.

2 lb ground beef
2 large onions chopped fine
4 to 6 ounces ketchup
2 to 4 ounces mustard

Brown onions and ground beef together
Do NOT drain
Add ketchup and mustard
Simmer untill it looks right
Add ketchup and/or mustard to adjust if needed

This recipe ( such as it is ) is over 60 years old, heritage I guess.